All, a while back I remember a thread asking whether the gravity of wort with protein still in suspension was different than the same wort clear. Well, I got a data point this weekend. I took the gravity of my Kentucky Common with a refractometer immediately after the boil, cooled, and got 1.053. Later I took the gravity again once the cold break had settled out and got 1.050. Can't generalize from one point but it seems that the protein in suspension in wort contributes to the gravity.